We were issued plastic earplugs in BCT at Fort Dix in the Summer of 1967, usually kept them in their container in the top button hole of our fatigue shirts. I recall an article by Bill Jordan in which he whole heartedly endorsed the use of hearing protection, said his last set of hearing cost over $1000. I think recognition of the value of hearing protection is a post WWII occurrence, I recall reading an article by Charlie Askins where he said cotton wads, cigarette butts, and in some cases whittled wooden plugs were what he and his peers relied on the 1930s,for those of us of later conflicts having the adrenaline pumping and all yelling at the top of our lungs made us oblivious to any ear damage. In Vietnam we were forbidden to use captured weapons and ammunition due to covert operations